The short version is you get an option in Excel that says "clean chart" and your Excel charts look better. Here is a visual of what the most basic Excel bar chart looks like before and after running the "clean" command.

This may seem like a slight difference, but it saves a HUGE amount of time cleaning up difficult visuals. My hat is off to the brilliant folks behind this excel charts visualization plugin! Visit that last link for the downloads and installation instructions. Really, wow.